Update to v6.0 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-6.0

Test: Boots on coral.
Test: Bionic unit tests pass.
Change-Id: I282de83f23b432bef58214108a93700bdadddf0f
diff --git a/libc/kernel/uapi/linux/btrfs.h b/libc/kernel/uapi/linux/btrfs.h
index 9f76d52..d73527e 100644
--- a/libc/kernel/uapi/linux/btrfs.h
+++ b/libc/kernel/uapi/linux/btrfs.h
@@ -59,7 +59,7 @@
   __u64 num_ref_copies;
   __u64 num_excl_copies;
   struct btrfs_qgroup_limit lim;
-  __u64 qgroups[0];
+  __u64 qgroups[];
 };
 struct btrfs_ioctl_qgroup_limit_args {
   __u64 qgroupid;
@@ -304,7 +304,7 @@
 struct btrfs_ioctl_search_args_v2 {
   struct btrfs_ioctl_search_key key;
   __u64 buf_size;
-  __u64 buf[0];
+  __u64 buf[];
 };
 struct btrfs_ioctl_clone_range_args {
   __s64 src_fd;
@@ -335,7 +335,7 @@
   __u16 dest_count;
   __u16 reserved1;
   __u32 reserved2;
-  struct btrfs_ioctl_same_extent_info info[0];
+  struct btrfs_ioctl_same_extent_info info[];
 };
 struct btrfs_ioctl_space_info {
   __u64 flags;
@@ -345,14 +345,14 @@
 struct btrfs_ioctl_space_args {
   __u64 space_slots;
   __u64 total_spaces;
-  struct btrfs_ioctl_space_info spaces[0];
+  struct btrfs_ioctl_space_info spaces[];
 };
 struct btrfs_data_container {
   __u32 bytes_left;
   __u32 bytes_missing;
   __u32 elem_cnt;
   __u32 elem_missed;
-  __u64 val[0];
+  __u64 val[];
 };
 struct btrfs_ioctl_ino_path_args {
   __u64 inum;
@@ -422,7 +422,8 @@
 #define BTRFS_SEND_FLAG_OMIT_STREAM_HEADER 0x2
 #define BTRFS_SEND_FLAG_OMIT_END_CMD 0x4
 #define BTRFS_SEND_FLAG_VERSION 0x8
-#define BTRFS_SEND_FLAG_MASK (BTRFS_SEND_FLAG_NO_FILE_DATA | BTRFS_SEND_FLAG_OMIT_STREAM_HEADER | BTRFS_SEND_FLAG_OMIT_END_CMD | BTRFS_SEND_FLAG_VERSION)
+#define BTRFS_SEND_FLAG_COMPRESSED 0x10
+#define BTRFS_SEND_FLAG_MASK (BTRFS_SEND_FLAG_NO_FILE_DATA | BTRFS_SEND_FLAG_OMIT_STREAM_HEADER | BTRFS_SEND_FLAG_OMIT_END_CMD | BTRFS_SEND_FLAG_VERSION | BTRFS_SEND_FLAG_COMPRESSED)
 struct btrfs_ioctl_send_args {
   __s64 send_fd;
   __u64 clone_sources_count;